Author
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Wang, Chien |
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Submitted to: Horticultural International Congress Proceedings
Publication Type: Proceedings Publication Acceptance Date: 8/7/1998 Publication Date: N/A Citation: N/A Interpretive Summary: Kale, collard and Brussels sprouts are green vegetables which are rich in vitamins, minerals, and antioxidants. They also provide dietary fiber which is important to our health. Unfortunately, These vegetables are very perishable and deteriorate rapidly after harvest. They turn yellow, lose freshness and turgidity within a few days. We have found that by using moist hot air treatment shortly after harvest and before cold storage, yellowing could be delayed and quality could be better maintained in kale and collard. This treatment also reduced losses of sugars and organic acids during storage. This research has the potential to benefit produce industry and consumers. Technical Abstract: The effect of heat treatment with moist air at temperatures of 40, 45, 50, or 55 C for durations of 0, 30, 60, or 90 minutes was studied in mature leaves of kale (Brassica oleracea L., Alboglabra group) and collard (Brassica oleracea L., Acephala group), and Brussels sprouts (Brassica oleracea L., Gemmifera group). The optimal heat treatment for kale was found to be at 45 C for 30 minutes and resulted in higher postharvest quality, delayed yellowing, and less decline of sugars and organic acids with later storage at 15 C. Collard treated with 40 C for 60 minutes had the best maintenance of leaf structure and latest onset of yellowing, compared to the other heat treatments. When temperature and duration exceeded tolerance levels, heat injury was observed. In some cases of heat injury, tissues maintained their green color but developed fungal infection. In Brussels sprouts, heat treatments caused no significant effects in the rate of senescence or storage quality. |
